As one of basic components of a railway vehicle, the coupling buffer has the advantages of rapidly connecting and disconnecting railway vehicles, transmitting vehicle tractive force, and improving vehicle safety and comfortability.
The telescopic hitch buffer device is positioned inside an air guide sleeve of the first carriage of a high-speed EMU to reduce air resistance during running when it does not work, and stretches out of the air guide sleeve for connecting trains if necessary. At present, all telescopic hitch buffer devices used in high-speed EMUs are foreign products, higher in price and longer in delivery period, in particular to supply of spare parts; it is necessary to develop and manufacture telescopic hitch buffer devices in order to solve the current situation that telescopic hitch buffer devices depend on importing from foreign countries and to fill in domestic blanks. Key technologies in manufacturing telescopic hitch buffer devices are extension driving, extension in place and locking, and unlocking functions.
Currently two kinds of telescopic hitch buffer devices in use are as below: one is a manual-operated telescopic hitch buffer device used in an EMU comprising 16 carriages, and the other is a pneumatic-driven automatic telescopic hitch buffer device used in an EMU comprising 8 carriages, both are foreign products. The extension driving of the foreign manual-operated telescopic hitch buffer device adopts an external gear and rack transmission, the unlocking mechanism is also an external one, the buffer system is relatively weak in absorbing impact energy, the overall structure takes up large space, and the extension driving structure is complex.